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Main Vents?

wsdave
Member Posts: 97
After reading Dan's books, We've Got Steam Heat & The Lost Art of Steam Heating, I've noticed some discrepancies with my one pipe steam system.
I'm hoping that someone can lead me in the right direction.
I have no vents on the mains. What I do have is a 2" riser that branches off in two directions - left goes 13 feet and right goes 18 feet. The only vent in the system is a #3 Vent-Rite mounted on a 90 degree elbow located on the dry return attached to the 18' run. There is no vent on the other dry return.
What size vents should be installed and where?
I'm hoping that someone can lead me in the right direction.
I have no vents on the mains. What I do have is a 2" riser that branches off in two directions - left goes 13 feet and right goes 18 feet. The only vent in the system is a #3 Vent-Rite mounted on a 90 degree elbow located on the dry return attached to the 18' run. There is no vent on the other dry return.
What size vents should be installed and where?
0
Comments
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For short mains like that
install a Hoffman #4A at the end of each main before it drops into the dry return. This may require drilling and tapping the pipes- have a pro do this if you're wary.
To Learn More About This Professional, Click Here to Visit Their Ad in "Find A Professional"All Steamed Up, Inc.
Towson, MD, USA
Steam, Vapor & Hot-Water Heating Specialists
Oil & Gas Burner Service
Consulting0 -
Main Vents
Thank you steamhead for your reply.
I've been "playing" with this sytem for about 5 years!
Yes - I'm stubborn!
I've also come to the conclusion that I will need a professional because whomever installed this system was a "knuklehead"!
The near boiler piping is all copper, they only used one of the boiler's two tappings, no header, etc, etc.
The system is about 50 years old and the mains will have to be extended to accomadate the vents.
I have a strong background in HVAC, mostly air conditioning, and I have worked with 1200 PSI steam in the Navy but, after reading Dan's books and reading posts from people such as you it would be prudent on my part to do this.
Thank you all for your dedication and thank you Dan for your books and providing a place to look for professionals.
I strongly encourage ALL home owners to read these books!
I will continue to visit the Wall.
Dave0 -
Shouldn't need to extend the mains
Just drill into the side of a fitting and tap the opening. This is fine when you're only running 2 PSI. Here's a shot of one where I used the existing holes- a better location would have been the side of the last radiator takeoff tee, seen at the right.
To Learn More About This Professional, Click Here to Visit Their Ad in "Find A Professional"All Steamed Up, Inc.
Towson, MD, USA
Steam, Vapor & Hot-Water Heating Specialists
Oil & Gas Burner Service
Consulting0 -
Main Vents
I see what you are saying but......
I was under the impression that the vents should be located at least 15" from the last riser and prior to the dry return.
My system has a 90 degree 2" to 1" reducing elbow right after the last riser, leaving only 3" - 4" to the elbow.
This elbow is attached to the main with a close nipple.
If your suggestion would work I'm willing to give it a try.0 -
It'll work
I've used it hundreds of times and never had a problem. Locating the tapping on the side of the last tee gets it away from the end of the main, and elbowing up gives you a slight rise above the main. I don't have a better photo to illustrate it though.....
To Learn More About This Professional, Click Here to Visit Their Ad in "Find A Professional"All Steamed Up, Inc.
Towson, MD, USA
Steam, Vapor & Hot-Water Heating Specialists
Oil & Gas Burner Service
Consulting0 -
Main Vents
Thank you for your time Steamhead.0 -
Dave, I have 2 4A vents
I bought these two vents and can't use them on my system (the runs are too long). I could send them to you. They are brand new - never out of the box. I paid $30 each - You could have them both for $40. You can reach me at email rg_blaine@hotmail.com.
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Thanks for the offer Ralph however, I already have two sitting on my workbench.
I just wanted to double-check the size.
Thanks again.0
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